Return To The University of Iowa

In 1950 and despite the flourishing of our high altitude work, the new director of APL, R. C. Gibson, split my assignment so as to include supervision of the residual proximity fuze group. I was competent to provide such supervision but had no interest in pursuing further developmental work on fuzes. I did the job but interpreted the split assignment as foreshadowing the termination of academic style research in geophysics at APL. A few months later I received a telephone call from Professor Tyndall, my former research mentor at the University of Iowa. He informed me that Louis A. Turner had resigned as head of the Department of Physics after four years and that he (Tyndall) had suggested me as a possible successor. I was thrilled by this prospect and soon thereafter made a short visit to Iowa City for interviews and a departmental colloquium. Several weeks dragged on after I returned to Silver Spring, with no news. I finally received a letter from Tyndall advising me that they had offered the position to the individual who was their first choice and were awaiting his response. Another few weeks of suspense came to an end when Tyndall called to offer me the position which would also carry the rank of full professor. At that time my wife of five years had been west of the Mississippi only once and considered Iowa to be terra incognito from the cultural point of view. Nonetheless, she agreed to support my decision whatever it might be. I then accepted the offer but told Tyndall that I would need six months to wind up my obligations at APL. This was agreed.

On a very cold first of January 1951, my wife and I with our then two young daughters arrived in Iowa City in our old station wagon pulling an even older trailer containing most of our earthly possessions. We plowed through the snow to move into a "barracks apartment", one of a cluster of small metal-sheathed buildings which had been erected during the war as temporary quarters for naval cadets and other personnel associated with the University. The sole source of heat was a cast iron stove which was fed fuel oil from an external fifty-five gallon drum by gravity flow through a small copper tube. The small living room could be made comfortably warm but the remainder of the apartment presented a challenging problem in heat transfer. However, the monthly rent was only $35.

I entered my new duties with enthusiasm and dedication. I had a zero research budget but the department had an excellent machine shop and two skilled instrument makers as well as a large stock of more-or-less obsolete but still usable electrical instruments.

With the help of George W. Stewart I got a small but very important grant from the private Research Corporation as seed money and started research on cosmic rays using balloon-borne equipment; and I recruited several able graduate students as collaborators. Soon thereafter, I wrote a proposal to the U.S. Office of Naval Research for measuring the primary cosmic ray intensity at high latitudes above the appreciable atmosphere, using small military-surplus rockets carried to an altitude of about 50,000 feet by a balloon and launched from that starting point to reach a summit altitude of some 250,000 feet. By this inexpensive technique, I hoped to resume high altitude research on a low budget. The proposal was accepted. Support by the ONR has continued without a break for the subsequent thirty-eight years and has provided the base for all of my research during this period.

In the summer of 1952, two of my students, Leslie Meredith and Gary Strein, our lab technician Lee Blodgett, and I made our first Arctic rockoon (rocket-balloon combination) expedition to measure the cosmic ray intensity above the atmosphere. We traveled on the Coast Guard ice breaker, the USCGC Eastwind, whose primary mission was the resupply of the weather station at Alert on the shore of the Arctic Ocean in northeastern Ellesmere Island. We released balloon-borne Deacon rockets from the heliocopter deck whenever we could persuade the captain to steam downwind for an hour while we inflated and released the balloon under zero relative wind conditions. After several failures we diagnosed and cured the problem and got a succession of successful flights to altitudes of about 200,000 feet at locations off the coast of Greenland -- the first research rocket flights ever made at such high geomagnetic latitudes. All of the instrumentation, including the telemetry transmitters and nose cones, were built in our own shop; a single Geiger-Mueller tube was the radiation sensor.

We reported our results with pride to the UARRP and set to work to refine the instrumentation using ionization chambers and scintillation counters as well as G.M. tubes.

During succeeding summers, Arctic rockoon expeditions on various ships were the heart of our work. These were led by Melvin Gottlieb and Frank McDonald. The 1953 expedition yielded a remarkable new finding, namely, the first direct detection of the electrons which, we surmised, were the primaries for producing auroral luminosity.

For a fifteen-month period 1953-54, my family and I took a leave from the University of Iowa to join Lyman Spitzer at Princeton University in an experimental program for investigating the confinement of hot plasma by a magnetic field in a twisted figure-eight shaped tube which he called a stellerator -- so named with the hopeful prospect of providing a demonstration of controlled thermonuclear fusion in deuterium and eventually in a mixture of deuterium and tritium. All of this recalled my Ph.D. thesis. I built and operated a crude model of such a machine, called the Model B-1 stellerator. (Model A was a previously-built smaller device of table-top size.) I demonstrated the validity of Spitzer's rotational transform of magnetic fields in the twisted toroid with a miniature electron gun and fluorescent screen and got plasma confinement times of a few milliseconds in a hydrogen plasma. The difficulty of making a much larger machine of this nature and, as it appeared to me, the remote prospect for achieving self-sustained fusion on a reasonable time scale convinced me to return to Iowa and resume my high altitude research, which was already yielding significant original results. This I did in August 1954.

Plans for the International Geophysical Year were by then being formulated, and my colleagues and I on the UARRP were eager to add investigations with rocket-borne equipment to these plans. I proposed to continue the rockoon program with further auroral, cosmic ray, and magnetic field measurements in the Arctic, equatorial latitudes, and the Antarctic. This program was funded by the National Science Foundation within its special IGY program. Our field work culminated in 1957 with two shipboard expeditions which I led. The first was aboard the U.S.S. Plymouth Rock from Norfolk to northwestern Greenland; the second, aboard the large icebreaker the U.S.S. Glacier from Boston via the Panama Canal to the Central Pacific and thence to Antarctica. Of the thirty rockoon flights which Laurence Cahill and I attempted during these two expeditions which ranged from 79°N to 75°S latitude within a four month period, twenty were successful in yielding high altitude cosmic-ray, auroral particle, and magnetic field data.